The present invention generally relates to constant velocity joints and more particularly relates to a light weight low angle fixed constant velocity joint having improved packaging and more efficient assembly.
Constant velocity joints (CVJ joints) are common components in automotive vehicles. Typically, constant velocity joints are used where a transmission of constant velocity rotating motion is required. The common types of constant velocity joints are plunging tripod, a fixed tripod, a plunging ball joint and a fixed ball joint. These types of joints are currently used in front wheel drive vehicles, rear wheel drive vehicles and on propeller shafts found in rear wheel drive, all wheel drive, and four wheel drive vehicles. The constant velocity joints are generally grease lubricated for life and sealed by a sealing boot when used on driveshafts or half shafts. Therefore, constant velocity joints are sealed in order to retain grease inside the joint and keep contaminates, such as dirt and water out of the joint. To achieve this protection the constant velocity joint is usually enclosed at the opened end of the outer race by a sealing boot made of a rubber, thermoplastic, or silicone type material. The opposite end of the outer race generally is enclosed by a dome or cap, known as a grease cap in the case of a disk type joint. The mono block or integral stem and race design style joint is sealed by the internal geometry of the outer race. This sealing and protection of the constant velocity joint is necessary because contamination of the inner chamber of the joint generally will cause internal damage to the joint.
A main function of the constant velocity joint is the transmission of rotational forces and torque. In the prior art constant velocity joint assemblies, a variety of bolted joint designs are used to assemble a joint to a propshaft or halfshaft within the automotive vehicle. The torque transfer generates heat by the internal friction of the joint along with other transmission inefficiencies. Generally, as the speed and torque increase the heat generation of the constant velocity joint also increases. Many of these prior art constant velocity joints are capable of operating at specific angles which can be anywhere from a few degrees all the way up to about 50 degrees. Many of these high angle constant velocity joints have a maximum angle requirement and have to meet specific durability, strength and fatigue requirements. Some of these requirements include strength and fatigue at angle, strength and fatigue in a straight ahead condition, and quasi static strength at angle. The design of the prior art joints allow for these joints to operate at such high angles based on specific designs for the outer race, inner race, cage and rolling elements of these prior art constant velocity joints. However, many of these prior art constant velocity joints that operate at high angles on wheel ends or the like generally are very complicated to design and install. Many of these prior art joints are positively retained to the stub shafts within the wheel end environment or inboard environment of a half shaft such that once the joint is put together the joint itself cannot be disassembled unless the entire half shaft assembly is removed and the fixed joint and bar shaft are damaged and/or destroyed. Furthermore, many of these prior art constant velocity joints that operate at high angles require very heavy components and very large components which increases packaging requirements and weight for these constant velocity joints. Also the complexity of installation and design of such joints increases the cost of the constant velocity joints to the manufacturers of the automotive vehicles.
Therefore, there is a need in the art for a constant velocity joint that can operate at high angles that includes a reduced mass constant velocity joint. There also is a need in the art for a constant velocity joint that reduces the packaging space needed for the constant velocity joint in the driveline of the automotive vehicle. Furthermore, there is a need in the prior art for a reduced cost and easier to install, design and produce constant velocity joints for the automotive vehicle. There also is a need for a constant velocity joint that is capable of being disassembled without disassembling the entire driveline half shaft environment.